Have you considered being a little less negative in here? You are always so incredibly negative, especially in this situation. From the minute you got your rejections, you were talking about leaving bad reviews and bad-mouthing the requester without even giving him a chance to fix it. Errors happen. This requester has been on Mturk a long time and has always been fair, in my opinion. It is always unfortunate when workers rush to trash the reputation of an established requester without even thinking about how this hurts all of us. It's painfully easy to see why so many requesters get chased away from here. Do you think requesters don't read these forums? Read their reviews? Do you think future requesters want to get involved with a site knowing workers are so quick to act so unprofessionally? I wouldn't want to post jobs on a platform knowing workers won't hesitate to sabotage my reputation, if I make a small error (or don't give into their reversal demands even if they actually are to blame).
He is trying to make things right. If you aren't one of the people he can track the issue to, have you considered that maybe you just fucked up? Workers make mistakes, too. I get rejections and I deal with them because sometimes, they're my problem. And, even if they aren't, acting without careful thought for the situation doesn't help anything. It certainly doesn't help the future of the platform and relationships with requesters.